Fluid measuring device



April 1935.

D. D. WILE FLUID MEASURING DEVICE Filed Dec. 19, 1 929 I Figai.

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, latented Apr. 9,193 I 2 "UNITED! PATENT. OF ICE 7 Daniel D. Wile, Detroit, Mich 'assignor to De trait Lubricator Company, Detroit, Mich., a corporationoflvlichigan I v Application December 19, 1929, "SerialNo. 415,259 15 Claims. -(Ol. 73-167) My invention relates to new and useful, ,im- 6, 'Lthe wiresfi being preferably of bismuth-and provements in means for measuring the state of the wires. 1 being preferably of aplatinum iridia fluid, and particularly'to'a novel apparatus or um alloy. The wires 6, I extend lengthwise of device for measuring the rate of flow of afluid. the member 4 with the hot junctions 8 positioned 6 i If a body is supplied with energy at aconstant adjacent the free end of member 4 and, spaced 6 rate sufficient to heat the body to a'temperature about the'periphery thereof and with the cold higher than the temperature of a, fluid, a state junctions 9 likewise spacedabout member 4 and or characteristicof which is to be measured, then extended toward the handle I. From the posi-.

there will bea heat-flowfrom the body to the tive terminal 10 of the thermopile 5 extends a 10 fluid. should the b dy b ositioned in a, flow- .lead wire II, and from the negative terminal I2 10 ing fluid, then the greater the velocity of the extends a l adf'wir l3, t e wi s H d I3 p fiuid, the more rapid will begthe transferof heat erahly passing along member 4 and through the to the fluid or'withdrawal of'heat from the. body han le bore 2. Fixed on the member -4; adj by the fluid and the lower will bathe temperacent junctions 8 is a heater element l4 of mateture of the body,until at infinite velocity the rialh vin a l w t mp ratur co flicie t of r 15 temperature or the body will be substantially s sta su h," r xamp as ana yf hr that of the temperature ofthe fluid. The tem-' mium, nick and irOh- The element 14 is P perature of the body will therefore be. indirably wrapped or coiled aboutthe end of memcation of the state of the fluid or of its velocity h 4 n r s the J nc ions 8 to aid in seif flowing. By employing m responsive t curing the thermopile tothe member 4, the turns 20 th temperature ofthe body whi hwiu a te f element-l4 being insulated from oneanother matically compensate for'variation in theternby Sh l the ,'Wh 0h lso serves to Seperature of the fluid, the state ofrthe fluid orof cure the coiled element in p i i n in cits velocity if flowing will be indicated by the refrom h terminals the element a e lead sponsive means irrespective of variation in tem- Wires w ch extend through the b of 25 perature of the fluid. r e member 4 and the handle bore 2. The thermopile h i ti e i t in th improved i I 5 and heater element [4 are preferably provided struction, and combination of parts, to be more with a guard member comprising a plate member fully described hereinafter; and the novelty of 11 c y Substantially U-ShaDed'inVeTted frame which will be particularly pointed out and 615- members l8 which are rigid" with member I1. 30 tinctly claimed; The handle member I fits and is secured in a In the accompanying drawing, to be taken ,1 central aperture IS. in the member [1, which has as-a part of this @speciflcation, I have fully and & depending Supporting flange 20 which engages clearly'illustrated a preferred apparatus embodythe member I. i I ing my invention, in which'drawing-Q A source of electrical] energy 2|, such as a dry 35 Figure 1 is tat-diagrammatic view ofmy appabattery, is provided for the element [4 and has ratus showing the electric circuits employed its negative pole or terminal connected to the therein; i i i i i heater lead wire IS, in which is positioned a Fig. 2 is an enlarged detail view, partially in .rheostat 22 for regulating and maintaining convertical central section, of a part of my appastant the current flow through the element I4. 40 rattle, and d W 2 Connected to the positive pole or terminal of the Fig. 3 is a view in section on the-line 3-3 of battery 2t is a wire 23=which is joined to the Fig. 2. e lead' wire II, the junction being connected to one Referring tothe drawing by characters of re'f- .end, of a resistance element 24. Connected to erence, l designates a base or handle member of the opposite end of the element 24 are W es 5, 45 tubular construction having a longitudinal bore 25 which connect to opposite'positive terminals 2 therethro'ugh. Fixed in one end of bore 2, as 21, 28 of an electric switch-29, preferably of the at 3, and p'rojectingfrom memberl, isa hollow double pole, double throw type. The wires 13 open-ended rod or-bar supporting member 4, and 16 are connected respectively to the oppopreferablyof material having a low thermaland site negativeterminals 3| 3| of the switch 29., electricalconductivity such, for'example, as'glass he b d Of the Switch 29 are Connected by I or hard rubber. Secured to the outer surface wires 32, 33 to the terminals of a galvanometer of member 4 by shellac or a like insulating me- 34, or the like, having a needle or pointer 35 dium, isa thermopile or multiple junction therrespons'ive to electromotive force and movable mocouple 5 composed of wires or strips of metal over a scale 36 calibrated in accordance with to convertthe galvanometer 34 into an ammeter for indicating the currentflow through the heater [4. A switch 38 is preferably incorporated in the heater circuit ior making and breaking the current flow through the heater element;

"Theoperation of 'my device is as follows: The

switch 38isclosed and the switch 29 is thrown .to connect-terminals 28, 3| to leads 33, .32, re-

spectively, the galvanometer being converted to anammeter by the resistances 31,- 38. The rheostat.v 22 is then adjusted to regulate the current flow through the heater element It to a constant predetermined value which will heat the element M to a temperature higher than the temperature otthe fluid, such that at zero velocity the electromotive force generated by the thermopile will move the needle 35 clockwise through its range of movement. When the heater current has been adjusted, contact is broken at leads 28 and 31 and is made by the switch 29 at contacts 21 and 50, which cuts out the resistance 31 and connects the galvanometer 34 in the thermopile circuit. The thermopile 5 will generate an electromotive force proportional to the difference between the temperature of the heater l4 and the temperature orthe fluid. Since thethermopile 5 will be positioned in the fluid, the cold junctions ;81 thereof will be at the temperav e of the fluid sothat the thermopile will automatically compensate forv any variation in temperature of the fluid, and the electromotive force of ihe'tfhermopile will be constant at any given fluid velocity, regardless of changes in the temperature of the fluid. At zero fluid velocity the heater II will be at its maximum temperature, causing. the maximum temperature difference between the hot and cold junctions 8, 9 of the thermopile 5,.resulting in generation of the maximum electromotive force which will be visibly indicated by the position of the galvanometer needle I! with respectto the scale 36. When fluid flows-over the heater l4 and the thermopile 5, the temperature of the heater M will decrease, due to the cooling action of the flowing fluid, which will result in'the generation of a smaller electromotive force by the thermopile with a consequent counterclockwise movement or change in the position of the needle 35, which will indicate the velocity of the flowing fluid. The scale 35 maybe calibrated in velocity units by moving the heater M and thermopile 5 through space at predetermined velocities and marking the scale 36 at the points to which the needle 35 moves for the difierent given velocities. The galvanometer 34 may be adjusted to read between anydesired velocities by means of the resistances 22 and 24 and comprises in conjunction with the thermopile'5 a thermoelectric measuring means! In initially calibrating the instru- -of the needle 35 and minimum velocities will be equal to the {of the resistance ment, the current flow to the heater I4 is regulated by the resistance 22 such that the throw between the desired maximum length of the scale36. Theresistance value of be biased orcounteracted by a portion of the I electromutive force of the heater circuit such that the resultant electromotive force of the moves in response to any 24 is then determined so that w the electromotive force oft'the thermopile 5 will mum velocity will be zero, thus changing the position to which the galvanometer needle 35 given velocity within the desired limits so as to bring the needle 35 onto the scale 36.

Although I have described my measuring device as adapted particularly for determining the velocity of flow of a fluid, it will be apparent from the foregoing description that the device is equally adapted for determining other fluid states since the response of the galvanometer is actuated by the electromotive force of the thermocouple which varies in accordance with the rate of withdrawal of heat by the fluid from the heated element. Thus, my measuring device, when the galvanometer scale is suitably calibrated, may be employed to indicate directly such other-fluid states for example as the absolute pressureor the density of a given fluid. The fact that a change or variation in any of these states or characteristics will cause a variation in the rate of withdrawal of heat by the fluid from the heated body or element results in a change in the temperature of the heated body with a corresponding change in the electromotive force of the thermocouple indicated by variation in the throw of the galvanometer needle. Calibration of the'galvanometer scale to read in density or pressure may be made by any of the well-known methods, of calibrating such scales.

What I claim and desire to secure by Letters Patent of the United States'is: I

l. A device for. measuring the velocity of a positioned in the flowing fluid and having means to maintain constant the current supplied to said element, thermal responsive means separate from said element and so positioned relative to said element as to respond to variation of temperature of said element due to the cooling action of the flowing fluid and adaptedto be positioned in the flowing fluid, electrically operated means for measuring. the variation in response of said responsive means and having a circuit controlled by said thermal means, said measurement indicating the velocity of the flowing fluid, and a resistance element separate from said heating element and common to each of said circuits for controlling the response of said electrically operated means to a given velocity. I

2. A device for measuring the velocity of a flowing fluid, comprising an electric circuit having a heating element therein adapted to be positioned in the flowing fluid and having regulatable means to maintain-constant the current supplied to said element, a second'electric circuit including a thermocouple adapted to be positioned in the flowing fluid and having its hot junction adjacent said element, a galvanometer element therein adapted to be positioned in the fluid and havingmeans to regulate and maintain constant the current supplied to said element, a thermocouple adapted to be positioned in the fluid and having its hot junction adjacent said element, a second electric circuit including a galvanometer in circuit with said thermotive to positive and negative to negative, and resistance means interposed between said connections whereby a portion of the electromotive force of said first circuit biases th'e electromotiveforce of said second circuit to regulate the response.

of said galvanometer to, the electromotive force of the thermocouple. V

4. A device for measuring the state of a fluid, comprising a rod member having an electric heating element secured to one end thereof, a thermocouple fixed to said member by said element and extending longitudinally of said rod member and having its hot junction in engagement with said element, an electric circuit having means in circuit with said element to maintain constant the current to said element, a thermocouple circuit, and means in said thermocouple circuit responsive to variation in the electromotive force of said thermocouple for indicating the state of the fluid.

5. A device for measuring the state of afluid, comprising a hollow rod member having an electric heating element coiled about andsecured to one end thereof with the element circuitlead wires extending through the bore of said member, a thermocouple fixed to and extending longitudinally of said rod member and having its hot junction positioned adjacent said element, an electric circuit having means in circuit with said element to maintain constant the current to said elementya thermocouple circuit, and means in said thermocouple circuit responsive to variation in the electromotive force of said thermocouple for indicating the state of the fluid.

6. A device for measuring the velocity of a flowing fluid, comprising a supporting member having a thermocouple extending longitudinally thereof with its hot junction adjacent one end of said member and with its cold junction intermediate the ends of said member, an electric heating element coiled about said member in overlying engagement with the hot junction .of the thermocouple to secure the thermocouple to said member, said element being spaced from the cold junction, an electric circuit having means in circuit with said element to maintain constant the current to said element, and a second electric circuit having means in circuit with said thermocouple and responsive to variation in the electromotive force of said thermocouple for, in-

' dicating in terms of velocity of fluid flow the variation in temperature of saidelement due to the cooling action of the flowing fluid.

'7. A device of the character described, comprising a tubular base member defining a hand grip, a hollow rod member fixed in the bore of said base member and projecting therefrom, an electric heating element carried by said rod memwires extending through the bores of said members, a thermocouple secured externally to said rod member and having its ,hot junction in thermalengagement with said the, cold junction of said heating element, 7 thermocouple being remote from said element,

and a guard frame surrounding said rod member.

'8. A device of the character described, comprising a base member, a rod member carried by and projecting from said base member, an electric heating element carried by the free end of said rod member, and a thermopile comprising a plurality of spaced thermocouples secured externally to said rod member and having their hot junctions in thermal engagement with said element.

9. A device of the character described, comprising a supporting member having a hand grip portion, a thermocouple extending longitudinally of said member and having its hot junction adjacent one end of said member, and an electric resistance heating wire carried by said member and overlying'said hot junction to secure said thermocouple to said memberl 10. A device of the character described, comprising a supporting member having a hand grip portion, a thermocouple extending longitudinally of said member and having its hot junction adja-- cent one end of said member, an electric resistance heating wire carried by said member and overlying said hot junction to secure said thermocouple to said member, and a guard frame surrounding said one end of said member to protect said thermocouple. l

11. In a device of the character described, a supporting member, a thermocouple supported by said member, and a heating element in thermal engagement with and tightly securing said thermocouple to said member.

12. A device for measuring the state of a fluid, comprising an electric heating element, means to supply current to said element, an electric measuring device, switch means to electrically connect said measuring device in shunt circuit with said heating element whereby to measure the current flow therethrough, a thermocouple having its hot junction adjacent said heating element and its cold junction spaced therefrom, switch means to electrically connect said measuring device in circuit with said thermocouple whereby to measure the electromotive force of said thermocouple, and a resistance element in circuit with said heating element and with said thermocouple, said resistance element being operable to regulate the response of the measuring device to the electromotive force of said thermocouple.

13. A device for measuring the state of a fluid, comprising an electric heating element, means to supply current to said element, a variable resistance means in circuit with said element and said first-named means to regulate the current flowing through said element, an electric measuring device, switch means to electricallyv connect said measuring device in shunt circuit with said heating element whereby to measure the current flow therethrough, a thermocouple having its hot junction adjacent said heating element and its cold junction spaced therefrom, switch means to electrically connect said measuring device in circuit with said thermocouple whereby to measure the electromotive force of said thermocouple, and a resistance element common to the heater circuit and the thermocouple circuit, said resistance element being operable to regulate the response of the measuring device to the electromotive force of said thermocouple.

14. A device for measuring the rate of withdrawal oi heat by a fluid from a heated element, comprising an electric circuit having an element therein heated by current flow and adapted to be positioned in the heat withdrawing fluid, a second electric circuit including a thermocouple having its hot junction positioned to be influ enced by the heat of said element, a galvanometer in circuitwith said thermocouple, and means common to said circuits for imposing a counterelectromotive force on the thermocouple circuit whereby to regulate the response of said galvanamed circuit and said second nanied circuit being connected together positive to positive and negative to negative, and electric resistance means Joining and electrically connected to said connections'whereby a portion of the electromotive force of said first circuit biases the electromotive force of said second circuit thereby to regulate the responseof said galvanometer to the rate of heat withdrawal from said element.

DANIEL D. WILE. 

